title: Mononuclear lanthanide complexes incorporating an anthracene group: structural modification, slow magnetic relaxation and multicomponent fluorescence emissions in Dy compounds.
abstract: Four mononuclear lanthanide complexes, [Ln(hfac)3(depma)(H2O)] [Ln(III) = Dy (1), Gd (2)], [Dy(hfac)3(depma)2]2·H2O (3) and [Gd(hfac)3(depma)2]·2H2O (4), have been obtained (hfac = hexafluoroacetylacetonate, depma = 9-diethylphosphonomethyl anthracene) by using one (for 1 and 2) or two (for 3 and 4) depma molecules to substitute coordination water molecules of Ln(hfac)3(H2O)2. It was found that the number of introduced depma ligands can modify the coordination geometry of Ln(iii) ions, showing a distorted biscapped triangular prism geometry in isostructural 1 and 2 and a distorted square-antiprismatic geometry in 3 and 4. Magnetic studies reveal that both 1 and 3 show field-induced slow magnetic relaxation under the applied dc field of 1000 Oe. The solid-state fluorescence measurements indicate the presence of multicomponent emissions in 1 and 3, including ligand-centered (LC) emissions from hfac and depma, and yellow emission from Dy(III) ions and only ligand-centered (LC) emissions in 2 and 4.
authors.affiliation: State Key Laboratory of Coordination Chemistry, Coordination Chemistry Institute, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P R China. dkcao@nju.edu.cn
authors.forename: Deng-Ke
authors.initials: DK
authors.lastname: Cao
authors.forename: Yan-Wei
authors.initials: YW
authors.lastname: Gu
authors.forename: Jia-Qi
authors.initials: JQ
authors.lastname: Feng
authors.forename: Zhong-Sheng
authors.initials: ZS
authors.lastname: Cai
authors.forename: Michael D
authors.initials: MD
authors.lastname: Ward